1. Field of the Invention
The present invention concerns a selective sorting harvesting machine, in particular for grape harvesting. It also concerns a sorting chain including this machine.
The sorting machine according to the invention is more specifically intended for sorting of grape harvest components, but this sorting machine can also be used advantageously for sorting of other berry or small fruit crops such as black-currant, gooseberries, huckleberries, bilberries, cranberries, cherries, coffee beans, or plums.
Because of the particularly advantageous application of the invention for sorting of grape harvest components, we are describing below an example of the implementation of this application, but we emphasize that this usage is by no means limiting.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
It is well known that between the harvest and actual startup of the processes and equipment for wine making, the grapes undergo various operations to eliminate debris that is undesirable for the elaboration of wines.
In most cases, regardless of whether the harvesting was done manually or by mechanical means (grape picking machines), the grapes are de-stemmed before and/or after a sorting operation.
When this occurs before the stripping, and in particular in the case of mechanical harvesting, the sorting operation may be performed manually on straight or vibrating sorting tables or mechanically. For example, by means of a sorting device mounted on the harvesting machine. In this case, the manual sorting allows for elimination of grapes that are rotten or not ripe enough as well as a certain volume of undesirable foreign matter such as leaves, leaf-stalks, twigs, insects and small animals.
On the other hand, one is aware (FR-2 795 599) of a sorter mounted on a harvesting machine and which features a travelling screen in the form of an endless belt and in proximity of its drop-off end there is an aspirator, this travelling screen being constituted by a number of tilting modules arranged one after the other. The sorter permits the extraction of a high percentage of leaves, grape stalks without fruit and other vegetable detritus. It also allows extracting the berries or grains detached from the stalks by the harvesting system and the juice coming from the bursting of a certain percentage of berries due to the action of the harvesting system.
The stem removal can be performed by different types of stalk separators or hull removers. The function of these devices is to clean up the grape harvest, whether it has undergone a first sorting or not. They also permit eliminating a certain percentage of foreign matter. In other words, the purpose of these devices is to separate the detached berries and the juice from other vegetable matter habitually picked up by the machine.
Complementary sorting, manual on a sorting table, or mechanized on an automatic sorting table or some other specific equipment is generally necessary downstream of the stalk removal, in order to eliminate if not all but at least most of the foreign objects still present such as leaf parts, leaf stalks, twig fragments, immature, botrytized or shattered grape berries and various debris (debris from supporting stakes, clips, insects, etc.).
After this complementary sorting, the harvest is composed of whole and healthy ripe berries; immature or shattered berries; crushed or burst berries; and bits of skin, stones and miscellaneous detritus.
To ensure the production of high gustatory quality, it is desirable to use only fully ripened, whole and healthy grape berries.
The configuration provides for achieving a qualitative separation of the berries into three categories, depending on their quality, so as to allow, if desired, separate vinification of each of them.
A technique that is proposed to obtain this result, involves dumping the grapes which have been previously de-stemmed and sorted—before and/or after the de-stemming—on a drum rotating around a horizontal axis. The berries are differentiated only by their consistency. A first category is constituted by whole grapes which do not adhere to the roll, a second category consists of burst grapes and debris which adhere to the roll but come unstuck from it by the centrifugal force generated by the rotation of the roll, and a third category comprising crushed grapes, skins and other debris which adhere to the roll and which are removed from it by a scraper. The grapes of the first category are directed towards a densimetric bath. The ripest grapes drop to the bottom of the tub and are picked up by a vintage pump, whereas the less ripe grapes and light debris remain on the surface, are evacuated with the components of the second and third categories.
A major drawback of such a technique is a qualitative insufficiency of the result obtained. Another notable drawback is the slowness of the process and low productivity which are incompatible with the large quantities of grapes harvested by modern harvesting machines, and the unfavorable repercussions on the cost of the wines produced exclusively from the selected grapes which are healthy, ripe and whole.
One goal of the present invention is to propose a sorting machine which permits to discriminate efficiently between the components of the grape harvest and to select from them the ripe, healthy and whole berries, at cadences compatible with the quantities of grapes harvested by means of harvesting machines, including the high-performing ones, or by mechanical harvesting processes of very high quality.
The sorting machine according to the invention is of the type which includes a feeder system conveying product to be sorted and which is unloaded at the downstream end of said feeder system, and which are differentiated by a vision system.
Such a device is for example described in the document EP-O 932 456 which describes a sorting apparatus comprising a sorting station and distribution conveyor that is steeply inclined towards said sorting station for transporting to the latter a flux of product to be sorted, from which conveyor the product is ejected when it arrives at the lower drop-off end and is being categorized during its free fall. The differentiating system comprising means to illuminate the product, means to analyze the light reflected by the product, and means to eject the product.
Document EP-O 705 650 describes a comparable sorting device featuring a conveyor belt dumping the transported product in the action zone of a sorting station operating during the free fall of the product and including an optic color sensor to optically detect the color of said product and an evaluation system to evaluate whether the color detected by the color sensor is or is not a predetermined color and to produce a differentiation signal according to the result of the evaluation, said sorting station including also an ejector that operates in response to the differentiation signal of said evaluation signal in order to modify or not the trajectory of the falling product.
The devices described in documents EP-O 932 456 and EP-O 705 650 are intended to eliminate foreign matter from the flow of product presenting itself in the form of grains or dry seeds such as: coffee beans, grains of rice, peas, hazelnuts, peanuts, plastic grains or similar products, by using differentiation systems based on the analysis of the color of the products constituting the flux to be sorted. These devices and systems are totally incapable of performing a qualitative separation of small fruit presenting itself in the form of juicy berries and of spherical shape, which actually have a tendency of aggregating together because of the sticky nature of their juices which are produced during the harvest or the de-stalking.